High-temperature oxidation resistance of alumina-forming ferritic alloys in a steam-containing atmosphere

In this study, the high-temperature steam oxidation resistance of alumina-forming ferritic alloys (AFF) alloys was investigated. A dense α-Al₂O₃ film, heterogeneously nucleated beneath pre-formed Fe₂O₃/Cr₂O₃ oxides, effectively suppressed oxygen diffusion into the substrate, resulting in significantly enhanced oxidation resistance compared to commercial austenitic stainless steels (ASS). Upon prolonged exposure at 700 °C in an air-10 % H₂O atmosphere, AFF alloys exhibited minimal weight change and no surface degradation, unlike conventional ASS alloys. These findings offer valuable insights into the design of cost-effective structural materials that require both high corrosion resistance and mechanical performance. Notably, the AFF alloys demonstrate a favorable balance between these physical properties, positioning them as strong candidates for commercialization in advanced energy systems.